26 October, 2010

Murray Darling Basin Plan

As I listen with interest to the media debate and the reporting of the meetings with irrigators, I am increasingly alarmed at misunderstandings and perhaps deliberate falsehoods. I am provoked to write the following because I am passionate about building an ever stronger Australia with a strong, sustainable agricultural sector. I take two things as a given. First, farmers above all others have a vested interest in not debasing the physical assets (environment) on which their long term future depends. Those who fail to do this inevitably fail economically and successful farmers repair the damage. Australian land is renowned for its recuperative capacity. Second, in a global context, Australia has a moral responsibility to maximise its food and fibre production, always providing this can be done sustainably.

More specifically, we need to recognise that the most significant feature of Australia's weather is massive variability. All of our Murray Darling Basin rivers on occasions stop flowing, entirely as a consequence of lack of rain. As Henry Lawson wrote, "they can be either muddy gutters or second Mississippi's". The "big wets" are surprisingly frequent, but totally irregular. It has been forever thus.

We also need to bear in mind that water is dynamic. It doesn't hang around and wait to be used. It either runs to the sea or to some wonderful inland wetlands, evaporates, or is used to grow things. There is no shortage of water in the world and Nature has given us a wonderful recycling system whereby salt water is continually converted to fresh water. There is, however, in many countries a limited supply of fresh water and in Australia in particular, we need to conserve water from the big wet events to even out the abovementioned variability. I see evaporation of fresh water as very wasteful. Some 70% of the Earth's surface is covered by (salty) oceans-plenty of water for cloud formation.

Where you have massive variability it seems to me to make little sense to debate using absolute numbers in respect to the aggregate level of desirable extraction limits or in stating flows. Averages can be very misleading. When absolute statistics are used they need to be be related to the highly variable flows.

The Plan
The Plan effectively blames extractions ("over allocated") for the extremely low river flows of recent years.  Farmers are being blamed for the drought. No wonder they are upset.

The Prime Minister has said "we cannot go on as we are". The Opposition Leader has said that "we are taking too much water out of our rivers". I do not accept these statements and believe they reveal a lack of understanding of how our system of managing irrigation actually works.

The two key terms are "Licenses/Entitlements" on the one hand and "Allocations" on the other. They are constantly confused in the current debate.

State Governments have issued "Licenses/Entitlements" to farmers, but the usage of these has to be triggered by the granting of "Allocations". Allocations are granted seasonally by Governments in accordance with available water. This is how variability is dealt with. When water is short, allocations are low or non-existent.

The Governments action in granting, or not granting, allocations is governed by a "water sharing plan" for each irrigation river in the basin. These water sharing plans take account of water availability, environmental, livestock and domestic needs before irrigation extractions are allowed. Whilst water sharing plans are hotly debated by people pushing the various competitive needs, it is a most sensible and effective approach.

However, of recent times there has simply not been enough water to go around and quite correctly it is irrigation extractions which have been severely constrained. Few realise that if it were not for the headwater storages, the Snowy Scheme diversions and severe restrictions on irrigation extractions, the Murray River would have actually stopped flowing altogether, as it has done under very dry conditions several times in recorded history. Through this drought we were able to keep it flowing and to maintain at least some water in the Lower Lakes at the mouth of the river as a result of these factors.

In my time with Clyde Agriculture I had the experience of being an irrigator and a flood plain grazier. For example, the Clyde property Oxley Station downstream from Warren is the largest property in the famous Macquarie Marshes. Properties such as this receive great benefit from what graziers term "beneficial flooding". Shallow flood water acting as natural irrigation with resultant prolific growth of natural grasses. It is great cattle breeding and fattening country. When water is short the "marsh graziers" invariably blame the upstream irrigators even when they also have no water. At Bourke, Clyde is an irrigator and when water is short downstream graziers invariably blamed the irrigators for taking it, even if they had been unable to extract water for months. It seems to be a quirk of human nature to blame other people rather than accept the power of Nature to dominate us all.

The Lower Lakes
One of the main arguments put forward to demonstrate that the Murray in unhealthy is the presence of acid sulphate soils as the fresh water in Lakes Alexandrina and Albert (the Lower Lakes) dries back. In discussing the Murray Darling Basin I often say "beware the South Australians", where the "blame factor" is most apparent. If you live in the driest State in the world's second driest continent (I understand Antarctica is the driest), and you only have one major river in your state (the Murray) and you live at the end of the stream, you are going to have a "hang-up"! From the time young South Australians are in short pants they are told that those awful farmers in Queensland, NSW and Victoria "take all our water". It is not an unfamiliar story around the world. It led Mark Twain to his famous comment "whisky is for drinking and water is for fighting over"!

The facts are that the South Australians have played the "victim's card" very well over the years and in terms of water sharing appear to get the best deal of any of the States in the basin. Furthermore, largely to support a small irrigation industry, which can be catered for in other ways, they converted the Lower Lakes into a permanent, highly inefficient, fresh water storage. Under natural conditions the Lower Lakes formed the natural estuary of the Murray River and depending on river flows, were sometimes fresh and sometimes salty. (See lakesneedwater.org).

Evaporation of fresh water from these lakes is enormous and it is truly outrageous that under dry conditions, upstream users are deprived of water so as to send large quantities of fresh water down to the Lower Lakes to mostly evaporate.  Under natural conditions salt water would have flowed in, but this is blocked by "The Barrages", as the series of weirs are called.

The problem of the Lower Lakes is, in my view, more a downstream problem than an upstream problem. However, the South Australians refuse to address anything other than what they term a "fresh water solution".

In dry times, before The Barrages were built,salt water has been known to come quite a long way up the main stem of the Murray.The Barrages, for much of the time, also prevent fresh water from entering the northern end of The Coorong.

The Lower Lakes will require much less fresh water if they are maintained in their natural estuarine state. In times of low flow the sea would always be able to keep water in the lakes at sea level and the problem of acid soils would be resolved.

From the foregoing I conclude that:-
  • we need to specify just what is meant  by the statement that we need to "restore health" to the system. Are we not simply calling the natural results of the driest period in our relatively short records,"unhealthy"? Australia has always been subject to long periods of very dry conditions;
  • buying back irrigation licenses/entitlements when there are no allocations will do nothing for our rivers (this really is "phantom water") and will only constrain production when water supplies are plentiful;
  • if our rivers are "over allocated", and to claim this we need to specify under what flow conditions we make the claim, then it is the water sharing plans which should be addressed. There is no point in withdrawing licenses/entitlements which under flood conditions may well be a means of flood mitigation; 
  • our forefathers did a great job of dealing with our massive run-off variability by building deep dams and diversions (Snowy) in the mountainous headwaters of our major temperate Australia river system. We need to make the cake bigger, by doing more of it;
  • we need to address the efficiency (read evaporation) of some of our water storages, including the Menindee Lakes. The Barrages at the mouth of the Lower Lakes should be removed and the Murray given back its estuary. The proposal to service irrigation by building a weir above the entrance to the lakes should be pursued.
  • the Water Act 2007 (Commonwealth) is excessively weighted towards environmental issues. It needs amendment, or at least be differently interpreted, so as to strike a proper balance.
Finally, from all of the above, one must conclude that the Murray Darling Basin Plan, as presently presented in the Guide, is deeply flawed.

David Boyd has spent over 50 years working in Australian agriculture. Prior to retirement in 2007 he was Chairman and a very "hands-on" CEO of Clyde Agriculture. Clyde was a major grazier (wool and beef), dryland grain producer (wheat) and irrigator (cotton). He has had a lifetime interest in water flows. 
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